The open() function of the downloads API opens the downloaded file with its associated application.

A downloads.onChanged event will fire when the item is opened for the first time.

This is an asynchronous function that returns a Promise.

Note: To use this function in your WebExtension you must ask for the "" manifest permission, as well as the "downloads" permission.


var opening =
  downloadId      // integer


An integer representing the id of the downloads.DownloadItem you want to open.

Return value

A Promise. If the request was successful, the promise will be fulfilled with no arguments. If the request failed, the promise will be rejected with an error message.

Browser compatibility

Chrome Edge Firefox Firefox for Android Opera
Basic support Yes No 48.0 48.0 33


This example opens the most recently downloaded item:

function onOpened() {
  console.log(`Opened download item`);

function onError(error) {
  console.log(`Error opening item: ${error}`);

function openDownload(downloadItems) {
    if (downloadItems.length > 0) {
      var opening =[0].id);
      opening.then(onOpened, onError);

var searching ={
  limit: 1,
  orderBy: ["-startTime"]

searching.then(openDownload, onError);

Example add-ons


This API is based on Chromium's chrome.downloads API.

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

Document Tags and Contributors

 Contributors to this page: wbamberg, Makyen, chrisdavidmills
 Last updated by: wbamberg,